The human immunodeficiency virus (HIV) is spread largely through sexual contact with an infected individual. Preventing the spread of HIV through designing interventions to help individuals choose safer sexual behavior is necessary. Primary Care Providers (PCPs) are in a unique position to intervene and have an impact on patients' health. Since the late 1980's, a number of organizations have recommended that PCPs act in their practices to help curb the spread of HlV and other sexually transmitted diseases (STDs). Studies conducted among primary are physicians show low rates (10%) of sexual and drug history assessment. None of the studies have used a comprehensive theoretical framework for understanding the relationships among providers' behavior and mutable variables which might have a direct effect on that behavior. In order to develop effective interventions to change clinicians' perceptions and increase the likelihood of sexual and drug history taking behavior and HlV/STD preventive counseling, we need a better understanding of how provider and patient beliefs, values, normative influences, perceived skill in counseling, practice characteristics and other factors affect these provider behaviors. An expanded version of the Theory of Reasoned Action (TRA) is used as the theoretical framework for this proposed research. Use of the TRA will allow the determination of actors directly affecting providers' behavior. Results from this research will lead to the design of intervention programs to increase PCPs sexual and drug history taking and HlV/STD preventive counseling behavior. The research will be conducted in Washington State with a sample of PCPs selected using multistage, luster, stratified probability sampling. PCPs will be surveyed to assess the determinants which impact individual provider's behaviors in regards to sexual and drug history assessment and HlV/STD prevention counseling behavior. In addition, for a subsample of providers (n = 200), patient's perceptions regarding their provider's behavior will be assessed. Patients will be surveyed in two groups. A randomly selected sample of patients from the subsample of PCPs will be surveyed with a mailed survey instrument. These patients will be used to corroborate provider's self reported sexual and drug risk assessment and HlV/STD prevention counseling behavior. In addition, selected patients and their providers will be surveyed after the patient's health maintenance visit with heir provider. Regression analyses will be conducted to identify the key beliefs, values, social normative influences, past experiences, perceived skill, critical events, and patients' beliefs and values that best predict rates of provider HlV/STD risk assessment and counseling behavior. Data from providers and patients will be linked. Analyses will be conducted looking at patterns within and across provider specialty and patient and provider gender groups. Further analyses will be conducted to compare groups on identified key variables and to determine which factors are amenable to intervention through educational methods.